Electric distribution system.



L. B. JONES.

ELECTRIC DISTRIBUTION SYSTEM.

nrmoumn rum) mn.1s,1913.

1981,7 19. Patented Dec. 16, 1913.

UNITED STATES PATENT OFFICE.

LEE B. JONES, OF KANSAS CITY, MISSOURI.

ELECTRIC DISTRIBUTION SYSTEM.

T all whom it may concern: Be it known that I, L an B. JONES, a citizenof the United States, residing at Kan sas City, in the county of Jacksonand State of Missouri, have invented certain new and useful Improvementsin Electric Distribution Systems, of which the following 1s aspecification.

This invention relates to a new system for the transmission anddistribution of electrical energy.

The invention relates particularly to a system in which controllingmechanlsms of suit-able nature are provided, whereby whenever a demandfor current is created at any point on the system the primemover whichdrives the electric generator will be brought into motion,.and willcontinue to run under its own power to deliver current to the system;and whereby said prime mover will continue thus to operate or functionas long as the demand for current exists, but as soon as said demandceases the prime mover will stop and come to rest. In other words, thesystem is one in which the starting and stopping ofthe prime mover isdependent upon whether or not there is a demand for current on thesystem. Such an arrangement is of peculiar applicability toindividuallighting or distribution systems. For example, it ispeculiarly adapted for use on farms, and the like, where it is necessaryto use a generating unit, but where, on ac- .count of the size of theunit or its location,

or on account of the inability to secure adequate and proper skilledlabor for its supervision, it is undesirable to use the ordinarygenerating unit which must be manually started and stopped.

The main object of the invention is to associate mechanisms, such asrelays, or the like, with a generating unit and electric distributionsystem in such a way that as soon as a demand is created for current onthe distribution system, the generating unit will Y Specification ofLetters Patent.

Application filed March 15, 1913.

Patented Dec. 16, 1913.

Serial No. 754,518.

in responding to the demands for current from the distribution system.

Other objects and uses will appear from a detailed description of theinvention which consists in the features of construction andcombinations of elements hereinafter described and claimed.

In the drawing, I have illustrated diagrammatically one setof mechanismsand connections for accomplishing all of the aforementioned as Well asother results The prime mover illustrated in the present case is aninternal combustion engine, and the dynamo of the generating unit isshown as being a direct current generator. The generator comprises thearmature l havin a series field winding 2 and a shunt field winding 8.In the system illustrated in the drawing, the electric distribution iseffected by what is known as a simple twowire direct currentdistribution, and for this purpose there are provided the mains 4 and 5,between which the load comprising, for example, aseries of lights 6 isconnected. Each light or load is illustrated as being controlled by itsindividual switch or button 7. When the system is in operation thegenerator supplies its current to the mains 4 and 5.

It is desired to so arrange and combine suitable mechanisms with thegenerating unit and distribution mains as to bring the generating unitup to speed when a demand for load is created at any point on the distribution system. For this purpose, I have provided a storage battery 8of comparatively small amperehour capacity, the ob j ect'and function ofwhich battery is to start the generating unit and bring it into motionwhen the demand for current arises. In this connection, I have provideda suitble starting mechanism which will turn the prime mover over thenecessary number of times to bring it into action, and for this purposethe battery 8 supplies current to such starting mechanism as soon as thedemand for current is created. In the par ticular arrangementillustrated, I have availed myself of the characteristics of the dynamoof the generating unit, and I use the same for starting purposes. To theabove end, I have provided a relay 9 within which are mounted the coils10 and 11. Although in the drawing I have shown these coils as locatedoutside of the boX of the relay 9, still it will be understood that, asa matter of fact, they are set within said box and act upon the relayplunger 12 carrying the leaf contacts 13 and 14. Although these contactsare both carried by. the same plunger, they are insulated from eachother for reasons to be hereinafter explained. The

' coil 10 is of comparatively light wireand of comparatively largenumber of turns, so that, even when carrying a small current, it willdevelop a considerable magnetomotive force,.suflicient in fact to liftthe plunger 12 with its contacts 13 and 14. 011 the other hand, the coil11 is of comparatively heavy wire and may have but few turns, so thateven when carrying acomparatively heavy current it will exert only asmall magnetomotivejorce, just suflicient in fact to retain the plunger12 with its contacts 13 and 14 in raised position when any load is beingdrawn from the mains 4 and 5. The two coils 10 and 11 are connected inseries by the lead 15, the coil 11 being connected to the main 4. Thecoil. 10 connects by the leads 16 and 17 and through the coils ofanother relay to one side of the battery 8. The other side of thebattery connects by means of the leads 1.8 and 19 to the other main 5,so that as soon as a circuit is closed between the mains, a localcurrent will flow around the circuit from the battery through the leads18 and 19 to the main 5, through a switch 7 and load 6 to the main 4,through the coil 11, lead 15, coil 10, leads 16 and 17, and the coils ofthe other relay back to the battery. This current will energize thecoils 10 and 11 of the relay 9, and by reason of the comparatively largemagnetomotive force developed in the coil 10, the plunger 12 will beraised thereby bringing the contact 13 into operative position; Thecontact 13 will engage the contacts 20 and 21, while the contact 14 willengage the contacts 22 and 23. The contact 20 connects by a lead 24 tothe lead 17 and the contact 21 connects by a lead 25 to one terminal ofthe dynamo. The shunt and series coils of the dynamo connect to one ofits terminals by the leads 26 and 27 respectively and the armature connects to said terminal by the lead 28. The shunt coil and armatureconnect to the other terminal of the dynamo by the leads 29 and 30respectively, and said terminal connects by the leads 31 and 32 with theleads 18 and 19. From the above, it will be seen that as soon as therelay raises its plunger in the manner just described, a current willflow around the circuit from the battery through 55 the leads 18, 32,and 31 to one terminal of the dynamo, thence through the armature andshunt coil in parallel to the other terminal of the dynamo and thencethrough the lead 25, contacts 23, 14, and 22, and lead 24, through thecoils of the other relay, and back to the battery. This current willserve to some .degree to excite the shunt coil of the dynamo. Thecontact 13 connects by a lead 33 to the lead 15, so that as soon as theplunger 12 rises, the coil 10 of the relay 9 will be shunted or cut outof circuit, but the magnetomotive force of the coil 11 which remains incircuit will be sulficient to retain the plunger 12 and contacts 13 and14 in raised position as long as current flows betweenthe mains 4 and 5.

There is provided a relay 34 having the coils 35 and 36. Although thesecoils are shown in the drawing as set away from the box of the relay 34,still it will be understood that, as a matter of fact, they are locatedwithin said box, andact upon the plunger 37 carrying the contact 38.When this contact 38 is raised it engages the contacts 39 and 40 toclose a circuit. Now the coil 35 is of comparatively small wire and ofcomparatively large number of turns, so that for a given current, acomparatively large magnetomotive force is developed by it, sufiicientin fact to raise the plunger 37 carrying the contact 38. On the otherhand, the coil 36 is of comparatively heavy wire and of small number ofturns, so that even when carrying-a comparatively heavy current, it onlydevelops enough magnetomotive force to sustain the plunger 37 with thecontact 38 in raised position. Under ordinary circumstances, the closingof the comparatively light load between the mains 4 and 5 would notcause a sufficient flow of current around the local battery circuit, togenerate enough magneto motive force in the coils 35 and 36 to cause thesame to raise the plunger 37. However, by reason of the simultaneousenergizing of the coils l0 and 11 of the relay 9, and the consequentraising of the plunger 12 with the contact 14 and the consequent closingof a local circuit through the generator armature and shunt field inparallel, a sufficient additional. amount of current will be drawnaround this local circuit to thereupon energize the coils 35 and 36 'toan extent suificient to cause the plunger 37 with its contact 38 to beraised and thus establish a connection between the contacts 39 and 40.The contact 39 connects by a lead 41 with the other side of the seriescoil 2 of the dynamo, and the contact 40 connects by means of a lead 42to a point between the coils 35 and 36. Now it will be seen that theinstant the relay 34 acts to raise its plunger and contact 38, a localcircuit leads 18, 32, and 31 to one terminal of the dynamo, through thelead 30 to the arma-' ture 1, through the lead 28 to the other terminal,through the lead 27 to the series coil, through the lead 41 to thecontacts 39, 38, and 40 through the lead 42, to the coil 36, and finallyback to the battery. This local circuit will place the armature andseries field of the dynamo in series with each other, energizing theseries field in such a direction as to'turn the dynamo over as a motorin the proper direction, and thereby cause the prime mover to commencetorotate and come up to speed. As the speed of the dynamo continues toincrease,

the current around the last mentioned local circuit will decreaseaccording to the well known characteristics of the series motor,

but the magnetomotive force of the coil 36 of, the relay 34 will remainsufficient to maintain the plunger 37 in raised position for the timebeing. When the generating unit finally commences to operate under itsown power, its shunt field 3 will build up in a proper direction tocause the generator to generate an electromotive force which will buckthe starting current just considered, so that the latter will rapidlyfall until finally the current flowing through the local circuit,including the series coil, will become so small that the magnetomotiveforce of the coil 36 will not be sufficient to retain the plunger 37 inraised posit-ion, and the latter will drop, thereby opening the startingcircuit. However, as long as any current is flowing between the mains 4and. 5, the coil 11 of the relay 9 will remain energized to retain theplunger 12 in raised position, and thereby maintain the circuit bet-weenthe contacts 21 and 13 closed, so

that the dynamo will be able to deliver cur- Thus the load circuit whenoperating normally will be as follows: from the armature through theleads 30, 31, 32, and 19 to the main 5, through the load to the main 4,through the coil 11 of the relay 9, through the lead 33 to the contact13, to the contact 21, through the leads 25 and 28 to the other side ofthe armature.

When the generating unit is operating at normal speed, the potentialbetween the leads 25 and32 will be equal to or slightly greater thanthat of the battery 8, sothat at such times the current flowing throughthe battery by means of the leads 17 and 18 will become zero, or willeven be reversed, depending upon theamount of previous discharge orcondition of the battery, so it will be seen that the battery will beautomatically recharged if necessary to compensate or make up for theenergy which was drawn off during the starting operation. It will,however, be seen that, during the normal operation when the generatingunit is operating at full speed, the battery is pracbetween the mains 4and 5 ceases the generating unit will stop functioning and will come torest, thereby saving fuel, luhricating oil, and wear and tear on theparts. In order to effect this result, I make use of the contact 14carried by the plunger 12 of the relay 9. This contact serves to controlthe flow of current to the igniter, and as long as the contact stands inraised position, current is supplied to the igniter, but when thecontact is dropped by reasonv of the nonenergization of the coil 11,which will take place as soon as the load is cut off, the ignitioncircuit will be broken, thereby stopping the prime mover- In thearrangement illustrated, the igniter is shown at the point 43. Itconnects by a lead 44'with the contact 14, and through a centrifugalgovernor 45 and lead 46 to the lead 32. Therefore, as soon as thecentrifugal governor 45 throws its contact into closed position, and aslong a the contact 14 is held in raised position, the current will besupplied to the igniter 43 for running the engine. As soon as the loadis cut off from between the mains, the plunger 12 will fall, therebyopening the ignition circuit and stopping the engine.

The centrifugal governor 45 is u'sed for the purpose of closing theignition circuit as soon as the engine reaches a desired speed, as thereis a certain class of internal combustion engines which will not startproperly, unless the ignition circuit is left open until the desiredspeed is reached. However, 'in the present arrangement, although thecontact 14 will rise in the first instance, the ignition circuit willnot be closed until the engine reaches -a predetermined speed ascontrolled by the centrifugal governor 45. This governor may also be soarranged as to retain the compression valves of the cylinders open untilthe desired speed of the engine is reached, thus making it much easierto start the generating unit than would be the case if it were necessaryto start against the compression.

It will be seen that when the system herein described comes into normaloperation the only unusual resistance between the generator and themains is the resistance of the coil 11. Inasmuch as this coil is madefrom heavy wire and has but few turns, its resistance is very small, andin fact practically negligible. It will also be seen that during thestarting operation the only unusual resistance encountered by thestarting current from the battery is the resistance of the coil 36. Thiscoil is also of heavy wire and few turns, so that the loss of energy ofthe starting current will be eX- tremely small.

It was previously stated that, owing to such relay will fall and thusopen the starting circuit. It will be seen that the fall of currentthrough the coil 36 will be further accelerated by the rise of thevoltage of the generator itself, so that in fact the current through thecoils 36 and 35 will fall to zero and may subsequently be reversed. Atany rate the voltage generated by the generator itself will cause such adrop of the starting current as to cause the relay 34 to release.

In the system herein disclosed I have provided means for giving anindication or signal as long as a current is flowing in the startingcircuit, so that in case the starting circuit should remain closed foran abnormally long time, the operator or user will be informed that anabnormal condition exists. For example, in case the gasolene supplyshould become exhausted, so that the engine would fail to pick up andrun under its own power, the prolonged duration of the alarm orindication would give a warning and notice of such fact. Such an alarmor indication may be infiuenced in any desired I manner by the presenceof a current in the starting circuit, or the alarm or indication may begiven by the operation of the starting relay 34. In the particulararrangement illustrated, I have adopted the latter provision, and havemade such provision that,

.as iong as the starting relay holds its plunger 37 in'raised posit-ionto close the starting circuit, the signal will be actuated. Theparticular arrangement illustrated comprises a bell or the like 47connected by a lead 48 with the lead 32 on the one hand and with themovable contact 38 of the relay 34 on the other hand. Obviously as longas said relay holds its contact in elevated position, the bell or otheralarm device will have its terminals connected across the battery andwill be actuated by current from the same.

Although in the particular arrangement illustrated I have shown a bellconnected in shunt with the dynamo starting circuit, still I do notlimit myself to the arrangement illustrated except as called for in theclaims, but I contemplate within the scope of my invention, as far asthis feature is concerned,

the use of any suitable form of signal,

whether visible, or audible, orotherwise, which will be actuated as longas current scribed.

continues to flow through the starting circuit.

A study of the herein described system will show that, in order to turnthe generating unit over in the proper direction, its series andparallel windings should oppose each other. However, in view of the factthat the series winding is not in operation during-the normal running ofthe system, it is seen that this feature is not a disadvantage becauseat such times the generator is operating strictly as a shunt-woundgenerator. For that matter two-series windings might be used if desired,one of which could be placed in the lead 25 so as to carry only the loadcurrent delivered to the mains, and the other series winding being usedonly for starting purposes.

Although in the present case I have illustrated a particular arrangementof relays and other mechanisms for causing the generating unit to bestarted and brought into action, and to be stopped accordin to whetheror not a load is demanded om between the mains, still I do not in anywise restrict myself to the arrangements illus trated and described,except as may be called for in the claims, but I include within thescope of my invention any arrangement of relays or other mechanisms andsuitable starting devices, whereby the generating unit will be broughtup to speed as soon as a demand is created for the current, and wherebythe generating unit will cease to function when that demand ceases.

I claim:

1. In an electric distribution system, the combination with a generatingunit com prising a dynamo electric machine and prime mover, anddistributing mains, of a 105 storage battery, a relay for connecting thesame to the dynamo electric machine for the purpose of running the sameas a motor for starting purposes, and a connection between the relay anda distributing main 110 for the purpose of energizing the relay withcurrent which flows between the distributing mains when circuit isclosed between the distributing mains, substantially as de 2. In anelectric distribution system, the

combination with a generating unit com prising a dynamo electric machineand a prime mover, and distributing mains, of a source of electricalsupply, a relay for connecting the same to the dynamo electric machineto run the latter as a motor for starting purposes, and a connection fordelivering current momentarily to the distributing mains from the sourceof electrical supply,

said relay being operable under the influence of said momentary currentfor the purpose of connecting the dynamo electric machine to the sourceof electrical supply for starting purposes, substantially as described.1 0

3. in an electric distribution system, the comblnatlon with a generatingunit comprising a dynamo electric machine and prime mover, anddistributing mains, of a storage battery, a relay having a coil inscries with a distributing main, a pairjofcontacts in said relay forconnecting one terminal of the dynamo electric machine to said main,another relay having one of its coils connected between one terminal ofthe battery and the first mentioned distributing main, a connectionbetween the other terminal of the battery and the other distribut ingmain, said last mentioned relay having a pair of electric contacts, acircuit including the battery dynamo electricmachine, and said contacts,and a second coil in the last mentioned relay interposed in the circuit, including the dynamo electric machine and battery, whereby closinga circuit-between the mains causes a flow of current from the batterythrough the' coils of both relays to connect the first mentioned main tothe dynamo electric machine and-to close the circuit, including thedynamo electric machine and battery, substantially as described.

4. In an electric distribution system, the combination with a generatingunit, including a prime mover and a dynamo electric machine, and a pairof distributing. mains, of a storage battery, a starting relay, a coilin said relay interposed between one terminal of the battery and adistributing main, a connection from the other terminal ofthe battery tothe other distributing main,

and a'starting circuit, including the dyna-- mo electricmachinejbattery, and contacts of said relay, whereby when a circuit isclosed between the mains, a local current flows from the battery throughsaid relay' coil to energize the relay to thereby close the startingcircuit, substantially as described.

5. In an electric distribution system, the combination with a generatingunit comprising a prime mover and a dynamo electric machine, and a pairof distributing mains, of a storage battery, a starting relay,connections for establishing a circuit, including the dynamo electricmachine, storage battery, and contacts of the startingrelay, a main linerelay, connections for establishing communication between a distributingmain and a terminal of the dynanio electric machine, and including.contacts of the main line relay, a connection between one distributingmain and one terminal of the battery, a coil of the starting relayinterposed between the other terminal of the battery and the otherdistributing main,

'whereby the closing of a circuit between the of the main line relayinterposed between through said coil to energize the main line relay forthe purpose of connecting the distributing main to the dynamo electricmachine, substantially as described.

6. In an electric distribution system, the combination with a generatingunit and distribution mains, of starting means for bringing thegenerating unit into operation, means for actuating said starting meanswhen a circuit is closed between the distributing mains, and signalingmeans for indicating the operation of the starting means, substantiallyas described.

7. In an electric distribution system, the combination with a generatingunit and distributing mains, of means for starting the generating unitwhen a circuit is closed between the distributing mains,'and means forindicating the actuation of the starting means, substantially asdescribed.

8. In an electric distribution system, the combination with a generatingunit, including a dynamo electric machine and means for driving thesame, and electric distribution mains, of a source of electricity, meansfor connecting saidsource of electricity to the dynamo electric machine,means for actuating said connecting means when a circuit is closedbetween the distributing mains, and means for indicating the actuationof the connecting means, substantially as described.

9. In an electric distribution system, the combination with a generatingunit, including a dynamo electric machine and means for driving thesame, and electric distribution mains, of a storage battery, means forconnecting the storage battery to the dynamo electric machine forstarting purposes, means for actuating the connecting means when acircuit is closed between the distributing mains, and a signal operableunder the influence of the connecting means for indicatin the actuationthereof, substantially as described.

10. In an electric distribution system, the combination with agenerating unit, includ ing a dynamo electric machine and means fordriving the same, and electric distribution mains, of a storage battery,means for connecting the same to the dynamo electric machine forstarting purposes when a circuit is closed between the distributingmains, and a signaling device operable under the influ ence of theconnecting means to indicate the actuation thereof, substantially asdescribed.

11. In an electric distribution system, the combination with agenerating unit, including a dynamo electric machine and means fordriving the same, and electric distribution mains, of a source ofelectrical supply, a switch for connecting the same to the dynamoelectric machine for starting purposes,

means for actuating said switch'when a circuit is closed between thedistributing mains, and a signaling device connected to the switch andoperable. during the period of closure of the switch, substantially asdescribed.

12. In an electric distribution system, the combination with agenerating unit, including a dynamo electric machine and, means fordriving the same, and electric distribution mains, of a storage battery,a switch for connecting the same to the dynamo'electric machine forstarting purposes, means-for actuating said switch to connect thebattery to the dynamo electric machine for starting purposes when acircuit is closed between the distributing mains. and a signaling deviceactuated by the closing of the switch and operable during the intervalof closure of the switch, substantially as described.

13. In an electric distribution system the combination with a generatingunit, including a dynamo electric machine having a series winding andmeans for driving the same, and electric distribution mains, of a sourceof electrical supply, and means for connecting the same to the dynamoelectric machine, including the series winding to operate the same as aseries motor for starting purposes when a circuit is closed between thedistributing mains, substantially as described. 14. In an electricdistribution system, the combination with a generating unit, including adynamo electric machine having a. series winding and means for drivingthe same, and electric distribution mains, of a source of electricalsupply, means for connecting the same to the dynamo electric machine,including a series winding for starting purposes, and means foractuating the connecting means when a circuit is closed between thedistributing mains, substan tially as described.

15. In an electric distribution system, the combination with agenerating unit, includ ing adynamo electric machine having a serieswinding and a shunt winding, and meansvfor driving the same, andelectric distribution mains, of a source of electrical supply, means forclosing a circuit, including the dynamo electric machine armature,series winding, and source of electrical supply, and means for actuatingsaid circuit closing means for starting purposes when a circuit isclosed between the distributing mains, substantially as described.

16. In an electric distribution system, the combination with agenerating unit, including a dynamo electric machine having a serieswinding and a shunt winding. and means for driving the same, andelectric distribution mains, of a storage battery, means for closing acircuit, including the armature and series winding of the dynamoelectric machine and the storage battery, and means for actuating saidcircuit closing means for starting purposes when a circuit is closedbetween the distributing mains, substantially as described.

17. In an electric distribution system, the combination with agenerating unit, including a dynamo electric machine and means fordriving the same, and electric distribution mains, of a storage battery,a starting switch for the purpose of connecting the battery to thedynamo electric machine for starting purposes, and a connecting relayfor connecting the dynamo electric machine direct to the distributingmains after it has attained a predetermined condition, substantially asdescribed.

18. In an electric distribution system, the combination with agenerating unit, including a dynamo electric machine and means fordriving the same, and electric distribution mains, of a storage battery,a relay operable under the influence ofa current flowing from thebattery to the mains for starting purposes, and another relay operableunder the influence of said current for the purpose of connecting adynamo electric machine terminal to a distributing main, substantiallyas described.

19. In an electric distribution system, the combination with agenerating unit, including a dynamo electric machine and means fordriving the same, and electric distribution mains, of'astorage battery,a starting relay, connections between the relay, battery, and dynamoelectric machine, a coil in said relay operable under the influence of alocal current flowing from the battery to the distributing mains,another relay, connec tions between a dynamo electric machine ter minaland a distributing main, and a coil in said relay operable under theinfluence of current in the distributing main, substantially asdescribed.

20. In an electric distribution system, the combination with agenerating unit including a dynamo electric machine and means fordriving the same, and electric distribution mains, of a source ofelectrical supply, a controlling relay, an actuating coil in said relayhaving a comparatively large number of turns, a holding coil in saidrelay having a comparatively small number of turns, connections forplacing said coils in series with each other, a connection from theouter end of one of said coils to a distributing main, a connection fromthe outer end of the other coilto one terminal of the source ofelectrical supply, a connection from the other distributing main to oneterminal of the dynamo electric machine, and a contact actuated by saidrelay for establishing a connection between the other distributing mainand the other terminal of the dynamo electric machine, substantially asdescribed.

21. In an electric distribution system, the combination with agenerating unit including a dynamo electric machine and means fordriving the same, and electric distrlbution mains, of a source ofelectrical supply, a controlling relay, an actuating coil in said relayhaving a comparatively large number of turns, a holding coil in saidrelay having a comparatively small number of turns, a connection forplacing said coils in series with each other, a connection from theouter end of one of said coils to a distributing main, a connection fromthe outer end of the other of said coils to the source of elec tricalsupply, a connection from one distributing main to one terminal of thedynamo electric machine, a switch actuated by said relay, andconnections from the other terminal of the dynamo electric machine andfrom the connection between the two relay coils to'said switch,substantially as described.

22. In an electric distribution system, the combination with agenerating unit including a dynamo electric machine and means fordriving the same, and electric distribution mains, of-a storage battery,a controlling relay, an actuating coil 1n said relay having acomparatively large number of turns, a holding coil in said relay havinga comparatively small number of turns, a connection for placing both ofsaid coils in series, a connection from the outer end of the holdingcoil to one distribution main, a connection from the other distributionmain to a terminal of the dynamo electric machine, a switch'operableunder the influence of the relay, a connection from the otherterminal of the dynamo electric machine to the said switch, and aconnection from the switch to the connect-ion between the two relaycoils, substantially as described.

23. In an electric distribution system, the combination with agenerating unit including a dynamo electric machine and means fordriving the same, and distribution mains, of a storage battery, acontrolling relay, an actuating coil in said relay adapted to develop alifting magneto motive force with a comparatively small current, aholding coil in said relay adapted to develop a holding magneto motiveforce with a comparatively large current, a connection for placing coilsin series with each other, a connection from the outer end of theholding coil to a distribution main, a connection from the otherdistribution main to one terminal of the dynamo electric machine, a controlling switch operable under the influence of the controlling relay, aconnection from the other terminal of the dynamo electric machine tosaid controlling switch, and

for driving the same, and electric distribution mains, of a source ofelectrical supply, awstarting relay, an actuating coil in said relayadapted to develop a lifting magneto motive force; with a comparativelysmall current, a holding coil in' said relay adapted to develop aholding magneto motive force with a comparatively large current, aconnection for placing both of said coils in series with each other, aconnection from the outer end of one of said coils to the source ofelectric supply, a connection from the outer end of the other of saidcoils to one distribution main, a connection from the other side of thesource of electrical supply to the other distribution main and to aterminal of the dynamo electric machine, a switch operable under theinfluence of said relay, a connection from said switch to the connectionbetween the two relay coils, and a connection from said switch to theother terminal of the dynamo electric machine, substantially asdescribed.

25. In an electric distribution system, the combination with agenerating unit including'a dynamo electric machine and means fordriving the same, and electric distributionmains, of a storage battery,a starting relay, an actuating coil in said relay adapted to develop alifting magneto motive force with a comparatively small current, aholding coil in said relay adapted to develop a holding magneto motiveforce with a comparatively large current, a connection for placing bothof said coils in series with each other, a connection from the outer endof the holding coil to one terminal of the storage battery, a connectionfrom the outer ter- 'minal of the actuating coil to a distribution.maln, a connection from the other terminal of the storage battery tothe other distribution main and to a terminal of the dynamo electricmachine, a switch operable under the influence of said relay, aconnection from said switch to the connection between both of saidcoils, and a connection from said switch to the other terminal of thedynamo electric machine, the actuating coil of said relay serving tolimit the value of a recharging current flowing from the dynamo electricmachine to the storage battery, sub- I stantially as described.

26. In an electric distribution system, the combination with agenerating unit including a dynamo electric machine and means fordriving the same, and electric distribution mains, of a source ofelectrical supply, a starting relay, a lifting coil and a holding coilin said relay, a connection for placing said coils in series with eachother, a connection from the outer end of one of said coils to thesource of electrical supply, a connection from the outer end of theother coil to a distribution main, a connection from the source ofelectrical supply to a distribution main and to one terminal of thedynamo'electric machine, a switch operable under the influence of saidrelav, a connec tion from said switch to one terminal of the dynamoelectric machine, and a connection from said switch to the connectionbetween the two coils, whereby when a circuit is closed between thedistribution mains current flows from the source of electrical supplythrough a circuit including both of the coils and both of thedistribution mains to thereby cause the starting relay to actuate saidswitch, and whereby when the dynamo electric machine attains normalcondition its electromotive force opposes that of the source ofelectrical supply to thereby reduce the current flowing through thecoils of the relay until said coils are deenergiZed to allow said switchto open.

27. In an electric distribution system, the combination with agenerating unit including a dynamo electric machine, and means fordriving the same, and electric distribu tion mains, of a source ofelectrical supply, a controlling relay, an actuating coil in said relay,a connection from one end of said actuating coil to a distribution main,a connection from the other end of said actuating coil to the source ofelectrical supply, a connection from the source of electrical supply toone terminal of the dynamo electric machine, a switch operable under theinfluence of the controlling relay, a connection from said switch to theother terminal of the dynamo electric machine, a connection from saidswitch to the first mentioned distribution main, an ignition device forthe dynamo electric machine driving means, a contact operable under theinfluence of said relay to make contact with one terminal of the dynamoelectric machine, a connection from said contact device to the ignitiondevice,

and a connection from the ignition device to the other terminal of thedynamo electric machine, substantially as described.

. LEE B. JONES. lVitnesses:

4 H. A. JENNER, W. R. JAMES.

